摘要

高速铁路列车产生的废水代表了一个具有抗生素抗性的微生物流动库。它含有丰富多样的抗药性细菌（ARB）和抗药性基因（ARGs）。采用厌氧/缺氧/好氧工艺、厌氧/缺氧/好氧工艺和臭氧消毒工艺，在中试规模的反应器中处理电动动车组高速列车每天1 m3的废水，研究了ARB和ARGs的去除情况。此外，用定量PCR方法研究了两种流动基因元件（intI1和Tn916/615）和五种ARGs（tetA、tetG、qnrA、qnrS、blaNDM-1和ermF）的高流行率。ARGs（tetA、blaNDM-1和qnrA）与intI1呈显著正相关（R2分别为0.94、0.85和0.70，P<0.01）。生物处理可显著降低Tn916/1545（减少2.57logs）和肠球菌（减少2.56logs菌落形成单位（CFU）/mL），但qnrS丰度增加（增加1.19logs）。臭氧消毒能进一步显著降低废水中ARGs和肠球菌，分别降低1.67-2.49和3.16 logcfu/mL。此外，食物相关细菌科可能含有机会或寄生性病原体（如冰碛素科、卡诺杆菌科和瘤胃球菌科）。本研究筛选出的肠球菌具有多重耐药性。我们的研究强调了减轻高速铁路列车废水作为移动源产生的抗生素耐药性的重要性。

Wastewater from high-speed railway trains represents a mobile reservoir of microorganisms with antibiotic resistance. It harbors abundant and diverse antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs). This study investigated the removal of ARB and ARGs in a pilot-scale reactor, which consisted of an anaerobic/anoxic/oxic process, anaerobic/anoxic/aerobic process, and ozone-based disinfection to treat 1 m3/day wastewater from an electric multiple unit high-speed train. Further, the high prevalence of two mobile genetic elements (intI1 and Tn916/615) and five ARGs (tetA, tetG, qnrA, qnrS, blaNDM-1, and ermF) was investigated using quantitative PCR. Significant positive correlations between ARGs (tetA, blaNDM-1, and qnrA) and intI1 were identified (R2 of 0.94, 0.85, and 0.70, respectively, P < 0.01). Biological treatment could significantly reduce Tn916/1545 (2.57 logs reduction) and Enterococci (2.56 logs reduction of colony forming unit (CFU)/mL), but the qnrS abundance increased (1.19 logs increase). Ozonation disinfection could further significantly decrease ARGs and Enterococci in wastewater, with a reduction of 1.67–2.49 logs and 3.16 logs CFU/mL, respectively. Moreover, food-related bacteria families which may contain opportunistic or parasitic pathogens (e.g., Moraxellaceae, Carnobacteriaceae, and Ruminococcaceae) were detected frequently. Enterococci filtered in this study shows multi-antibiotic resistance. Our study highlights the significance to mitigate antibiotic resistance from wastewater generated from high-speed railway trains, as a mobile source.

https://sciencedirect.xilesou.top/science/article/pii/S0045653519327249